The preparation technology of ultrafine hexanitrostilbene (HNS) by recrystallization method was presented. The high-dispersed explosive solution was splashed into low-temperature water and the fitting surfactant was added at the same time. Ultrafine HNS was obtained with specific surface area 23.00 m²·g^-1, mean diameter 0.365 μm and purity 98.5%.